Sipeed Teases a $40 Single-Board Computer with Fully-Ratified RISC-V Vector Extensions

Sipeed has posted images teasing a new single-board computer based on a RISC-V processor boasting the ratified RISC-V Vector Extension 1.0 — something which should give a considerable boost to on-device machine learning and artificial intelligence workloads.

"What about [a] 1.6GHz RISC-V C908 chip with RVV1.0," Sipeed posted to its official Twitter account this week, referring to Alibaba's T-Head XuanTie C908 RISC-V core design. "Do you want a C908 SBC [Single-Board Computer] $30~$40?"

What makes the chip showcased by Sipeed interesting is that it's primary core, which runs at 1.6GHz, includes the RISC-V Vector Extension (RVV) 1.0 — the fully-ratified version, rather than the earlier pre-ratification 0.7.1 release which at the time of writing was the only version to have made its way into commercially available silicon. As a result, the chip should boast a big boost in performance for applications which can make use of vector acceleration — like on-device machine learning workloads.

Sipeed has been unusually silent on precise details surrounding the chip on which it plans to build a single-board computer, but a partially-redacted block diagram released by the company suggests it's an as-yet unannounced Canaan Kendryte chip — complete with Kendryte Processing Unit (KPU), a dedicated machine-learning accelerator with 2MB of static RAM (SRAM).

The block diagram also reveals a second processor core, running at 800MHz and without the RVV extensions, a security subsystem with true random number generator (TRNG), a power management system, a multimedia subsystem with 3D depth engine and 2.5D graphics processor, support for DDR3L,LPDDR3, and LPDDR4 memory, an image signal processor (ISP) block, and two USB 2.0 ports, two SD/eMMC peripherals, SPI, I2C, UART, and up to 64 general-purpose input/output (GPIO) pins including six pulse-width modulation (PWM) channels and a 12-bit analog to digital converter (ADC).

In a post to Reddit, former SiFive developer Bruce Hoult revealed another trick up the chip's sleeve: "[It] supports running RV32 [32-bit] code in User mode (only) on an RV64 [64-bit] core," he claims. "This is common on x86 and Arm but I don't know of any other RISC-V core that can do this. Arm, btw, has dropped this feature from their 2023 and on Armv9-A cores. No question, I'll be first in line to plonk down $30-$40 for such a machine!"

Sipeed has not yet offered a launch schedule for the new board, with interested parties advised to follow the company's Twitter account for more information when it's available.